High speed telegraph system



Jan. 5, 1943- s. APPERLEY HIGH SPEED TELEGRAPH SYSTEM Fil ed Sept. 27,1959 2 Sheets -Sheet 1 l 1 i i lNVENTOR ATTORNEY Jan. 5, 1943. s.APPERLEY 2,307,099

HIGH SPEED TELEGRAPH SYSTEM -Filed Sept. 27, 1939 Z-Shaats-Sheet 2 PlNVENTO R 650%?RLE Y BY ATTORNEY Patented Jan. 5, 1643 HIGH SPEEDTELEGRAPH SYSTEM *ourne, Victoria, Australia,

aspire t of;

gnments, to Radio Cor- New York, N. Y.

E7, 1939, Serial No. 296,758

in AQBu suA-\Q September 27, 1938 4 Claims.

This invention relates to high speed telegraph systems and moreparticularly to means for materially increasingthe eifective speed oftheir 'operation.

In one known automatic telegraph system, received signals are caused toactuate a re-periorating machine which records the signals in the formof perforations in a moving tape which is then caused to actuate aprinting machine to convert the signals to Roman characters, oralternatively, to actuate a second transmitter where it is desired torelay the message over a second channel.

In such known system the working speed is limited to that at which anyone function in the sequence of operations can be performed. In practicethe maximum speed of operation is governed by that of the re-perforatingand/or printing machine.

If the main signalling channel comprises a radio link, speeds greatly inexcess of the maximum speed of such printing systems are possible overthat portion of the system. It is in fact common practice to transmitand receive signals on radio circuits at speeds up to 300 words perminute, and such signals are usually recorded in the form of inkmarkings representing Morse charscters or otherwise, on a paper tape, bymeans of an lmdulator.

The speed of signalling over a radio channel is usually governed byatmospheric conditions, prevailing at any given time, and as suchconditions may vary considerably over a given period, it is evident thatif delays are to b avoided, advantage should be taken of those periodswhen conditions are favourable to operate the circuit at maximum speed.This means that during periods of good reception when the signallingspeed exceeds the maximum at which automatic re-perforating, printing orre-transrnission is possible, it becomes expedient to transcribemanually the message from the undulator tape; or, if the message is tobe re-transmitted over a second channel, to prepare manually aperforated tape.

It is an object of the present invention to provide means for overcomingthe above difficulties and limitations, and to enable a telegraph systemto operate automatically at the speed of the fastest link in thesignalling channel.

More specifically it is an object of this invention to provide means forconverting graphical representations of Horse or other code charactersto corresponding electrical impulses and to cause said impulses tocontrol a transmitter or automatic printing apparatus.

The invention comprises means for receiving and recording telegraphsignals in the form of ink markings or otherwise on a paper tape, meansincluding a light source and photoelectric cell for converting the saidmarkings to corresponding electric impulses, and means for utilising thesaid impulses to actuate or control one or more automatic printinginstruments or further transmitters.

In cases where it is desired to convert automatically the receivedsignals to Roman characters at the receiving station, the signals arereceived and recorded as ordinarily on an undulator tape at the maximumspeed of the signalling channel and undulator. In accordance with thisinvention the undulator tape is then divided into suitable lengths andthese are fed separately to individual scanning devices whereby therecording on the tape is converted at a suitable speed to electricalimpulses which are replicas of the received signal impulses, and used toactuate a plurality of automatic printers.

In cases 'where it is desired to re-transmit or relay the message over afurther circuit the converted signal impulses may be caused to actuatere-transmltting apparatus.

In order to convert the recorded signals on the undulator tape toelectrical impulses the said tape is caused to pass in close proximityto a suitable source of illumination, the light from which is directedonto the markings on the tape and is then reflected to control aphoto-electric cell, the output from the latter being amplified to astrength suitable to operate a reperforator, automatic printer ortransmitter.

For a more complete understanding of the invention and the manner inwhich it is to be carried into eil'ect, attention is now directed to theaccompanying drawings, in which:

Fig. 1 is a diagrammatic representation of a light system arranged inaccordance with a preferred application of this invention, and

Fig. 2 is an isometric view serving to show the construction andoperation of one type of scanning head suitable for use in conjunctionwith the light system of Fig. 1.

Referring to Fig. 1, light rays from a light source 3 are concentratedby means of a condenser 4 onto a diaphragm 5 having an aperture 1. Theimage of the aperture 1 is focussed by means of a lens or optical systemi onto a tape it bearing the signal markings 28 (Fig. 2) which are to beconverted into electrical impulses and which, as they pass the apertureI5, are exposed to the light rays irom the source 3. The signal markings29 on the tape H are such as will cause a variation in the intensity ofthe light reflected therefrom. The light rays which are reflected fromthe signal tape H are focussed by means of a further lens or opticalsystem 9,

' ture i between the light source 3 and the aperture i5 is described.Whilst this is the preferred arrangement it is to be clearly understoodthat the aperture 1 may be dispensed with and light rays from the lightsource 3 iocussed onto the aperture l5 direct if desired.

In practice, it is preferred that the light source 3, condenser 4,aperture 1 and lens 6 of the light source (also the light sensitive cellIn and its associated lens 9) should be adjustable with respect to thetape H in the aperture II.

The aperture I5 is itself, in the present example, arranged forindependent adjustment, such that its position with respect to the tapeH may be varied in a direction coincident with the movement of the tapel4 and also in a direcion at right angles to the movement and in theplane of the tape it. This independent adjustment oi the aperture l5compensates for any mis-alignment of the components employed fordirecting the light rays onto the aperture I5. Further, it enables theaperture is to be adjusted to that section of the incident light beamwhich contains the greatest concentration of light rays, and so ensuresthatoptimum amount of light is reflected to the light sensitive cell I0.

The components forming the light system oi Fig. 1 may be mounted in anyconvenient and well-known manner such as will enable them to i'ullfiltheir individual functions in directing a concentrated beam of H nt ontothe aperture l5, from the light source 3, and producing the desiredresponse by the light sensitive cell 80 to light rays which arereflected from the signal tape H in the aperture IS.

The light system of Fig. 1 is preferably enclosed so as to protect thelight-sensitive cell IO irom the influence of extraneous light. Thoseparts of the system which are exposed to the light rays are preie'rablyblackened or otherwise treated to prevent undesirable reflections on thelight sensitive cell it.

The aperture t5 and associated lighting system, is located behind thescanning head of Fig. 2 in such a manner that the tape l4, carrying thesignal markings 29 which are to be converted, passes over the aperturel5, and in the course base member 23.

markings are on that side of the tape H which 'is adjacent to theaperture II.

The tape It runs in a groove 30 which is provided in the tape came! I!in order to prevent undesirable lateral movement of the tape ll.

The said tape is tensioned in the runnin groove ber 21 (which issupported for angular rotation in a direction at right angles to themovement of the tape I4) by means of supports 25 which are attached toor form an integral part of a sliding The mounting of the gate ii andtensioning springs I2 is such that in the of its progress the signalmarkings 29 on the tape it produce a corresponding variation in theintensity of the light rays reflected from the aperture it onto thelight sensitive cell 63.

Referring now to Fig. 2, the tape i4, carrying the signal markings 29which are to be converted, is passed over the aperture is through a tapecarrier I! in a manner such that the said signal 5 effective position ofthe lever II, as shown in Fig. 2, the inner surface oi the gate H aswell as the tensioning devices I: contact with the surface of the tape94. The pressure of the gate ii and the tensioning devices I! on thetape H is adjustable by means of the adjusting screw ii, which passesthrough the gate Ii and projecting beyond the inner surface thereofpresses against the carrier plate ll. The pressure of the gate l I andtensioning means l2 on the tape ll should be such as wiil substantiallyeliminate undesirable movement of thetape H in front of the aperture iiwithout placing too great a load on the motive means propelling the tapethrough the carrier H, or imparting such tension as would retard thefree movement of the tape and result in breakage thereof.

The carrier :1, as well as the gate supports 2!,

is fixedly mounted on the sliding base 23, which is supported in-guides2d, 23 for movement in a direction at right angles to the movement ofthe tape H.

Depending upon the nature of the graphical signal representations on thetape H it may be necessary to adjust the position 01' the latter withrespect to the scanning aperture II to permit scanning of any portion ofthe tape betweenits two side edges. For'example, the signal markingsindicated on the tape H are those produced by an undulator. The side ofthe marking indi cated by M is the marker signal, whilst that shown as Sis the space signal. I! it is desired to scan either one of these sidesfor the purpose of producing corresponding electrical impulses,

the tape H must be moved to one side or the other to bring the relativeportion thereof over the aperture 85. 1 This involves the bodilymovement in a lateral direction of the tape carrier H and its associatedapparatus. This adjustment is provided for in thepresent example by thelever is. This lever is pivotally mounted on the fixed member 26 forangular rotation in a horizontal plane and carries on its under side acam (not shown), which projects into an elongated slot is in the slidemember 23 supporting the carrier ill and gate ii.

.When the lever id is in the position shown in Fig. 1, the centralportion, of the tape it is located over the aperture 55. Psotationalmovvment of the lever is in a clock-wise or anti-clockwise direction willshift the carrier ii laterally with respect to the aperture l5, and toone side or the other depending upon the direction of movement of, 58.The lever it may be locked in screw 28, which tightens the bearingwherein the lever ll pivots.

The aperture is is a longitudinal slit in a rectangular receptacle 8(Fig. l) which is dimensioned to fit into an aperture in the member anda slot in the carrier H in a manner such as will bring the aperture ISin contact with the tape it. In the present example the external I 3 Incarrying out the invention the aperture II may be arranged to scaneither the upper surface of the receptacle 8, which contacts with thesignal tape i4 and in which also the aperture i5 is located, is convexand protrudes through apertures in the slide member 23 and the carrieri! into a concavity in the gate ii.

To facilitate lateral movement of the carrier H, the aperture in theslide 23 and carrier I1 is extended in a lateral direction to an extentnecessary to provide for the full lateral movement of the carrier II aspreviously described.

The operation of the arrangement is as follows:

Signal markings 29 representative of the intelligence to be conveyed areimprinted on a tape i4, either manually or electrically. The marking 29may be straight Morse characters or undulating as for example thoseproduced by signal responsive instruments normally employed in highspeed telegraph systems and commonly known as undulators.

The lever i3 is operated to lift the gate Ii and associated tapetensioning devices II.

The tape it is passed through the groove II in the carrier plate II in amanner such that the signal markings II on the tape ll are on that sidewhich is adjacent to the aperture I.

The end of the tape i4 is attached to some form oi motive means (notshown) generally employed tor-pulling the tape through the carrier. The

lever I8 is operated to line up the aperture I! with that portion of thesignal marking which is to be scanned. The gate ii and tensioning meansI! are now closed on the tape it and are held in position by a springcatch or other suitable means (not shown). The tension of the gate ii isadjusted by means of the screw it to suit the thickness of the tapeemployed.

As previously stated, the light rays from the light source 3 areiocussed onto the aperture is and the rays reflected from any matterappearing therein are iocussed onto a light sensitive cell II, which isconnected in the input 0'! a suitable ampliiier 3i.

Asthesignalmarkings Ilonthetapell pass over the aperture II, theintensity 0! light or lower horizontal sections.

It is further possible by the use of two apertures each having its ownlight system as described in Fig. l, to scan simultaneously both theupper and lower horizontal portions of the tapes and to utilise theconverted electrical impulses in the output oi each unit to carry outindividual functions or to act as a check one against the other.

As an example of the operation of a system embodying the presentimprovements, it will be assumed that the speed of the signallingchannel is 300 words per minute, and that of the printer orre-transmitter 100 words per minute.

In these circumstances three scanning units would be employed. The tapefrom the undulator produced at 300 words per minute would be dividedinto suitable lengths and individual lengths ted to. individual scanningdevices so that the speed of the whole system would then be 300 wordsper minute and the system would becompletely automatic in operation andthere would be no necessity to transcribe manually.

I claim: i

1. A scanning device for tape which has signal markings thereon,comprising a tape guide member, an apertured gate, means for moving thetape longitudinally past the gate aperture, means for positioning thegate in either or two alternative fixed lateral positions with respectto the guide member, means-10! directing light through the aperture ofthe gate thereby to scan a portion of the tape to one side only of itslongitudinal center line, and photo-electric sensing means responsive tovariations in the intensity of light reflected by said tape andoutwardly reflected thereirom varies in dependence. upon the variationsof the signal markings on the tape. This variation in intensity of thereflected rays impinging on the light sensitive cell ll producescorresponding current variations in its output circuit, which areamplified in the associated amplifier 3i and utilised to actuateor-control a-printing instrument, re-periorator or further transmitter.

-Where signal marked tape, which is produced by a signal operatedundulator, is employed, that portion M of the markings I! on theundulator tape I, which lies closely adjacent to a line drawn throughthe upper horizontal section of the markings, represents a graphicalreplica oi the signals received, whilst that portion s of the markingswhich lies adjacent to ,a line drawn through the lower horizontalsection of the markmgrepresents the spadngperiods between the signalcharacters of the received signals.

through said aperture.

2. A device according to claim 1 in combination with a tape bearing agraphic representation' of marking and spacing signals, said gatemovingmeans being adjustable to scan either the marking or the spacingelements 0! said signals.

3. A telegraph-tape scanner having a tape guide member and anaperturedgate; an optical system including a light source arranged toilluminate the tape area which is framed by the aperture in said gate, aphoto-electric device disposed in the path of light rays reflected bythe tape through said aperture, said tape being marked with telegraphsignals, and means for laterally shifting the position or said gate intoone or the other of two fixed positions, thereby to sense apredetermined longitudinal track on said tape.

4. A telegraph tape scanner having an aperdistinctively responsive toreflections or light through the aperture of said gate, a tape bearingmarking and spacing indicia which are disposed thereon in two separatelongitudinal tracks, said indicia being selectively exposahle to lightfrom said source through said aperture in dependence upon the lateralposition of said tape with respect to said aperture, and means formoving said tape longitudinally past said aperture.

onoacr:

